Premenstrual syndrome (PMS) has been defined as a condition characterized by symptoms which recur in the late luteal phase of successive menstrual cycles, but are normally absent during menses and early follicular phase [K. Dalton et al., "PMS: The Essential Guide to Treatment Options; Thorsons, ed., London, England (1994)]. The symptoms associated with PMS range in severity from cravings for sweet or salty foods to headaches and exhaustion to depression, mood swings and irritability.
In its more severe manifestation, women who suffer from PMS are unable to maintain jobs because of their cyclical anger or inability to concentrate caused by the disease. In some individuals, PMS is so severe that it causes suicidal and homicidal feelings that, in some cases, are actually acted upon. It has been estimated that between 20 and 40 percent of menstruating women suffer from PMS symptoms severe enough to interfere with their normal daily activities [D. Rovner et al., Premenstrual Syndrome, American Council on Science and Health 1986].
To this day, the medical community is still not universally agreed that PMS is a medical disease. This has led to misdiagnosis and mistreatment of various PMS symptoms as purely psychological disorders. Moreover, certain PMS symptoms may also be observed in other disease states, leading to complications and difficulties in accurate diagnosis.
The biochemical changes responsible for PMS are still uncertain. Progesterone levels have been implicated in the disease, but studies attempting to correlate plasma progesterone levels and PMS have reached contrary conclusions. Some studies suggest that PMS is correlated with higher progesterone levels [K. N. Muse et al., N. Engl. J. Med, 311, pp. 591-93 (1984)], others suggest a correlation with lower progesterone levels [K. Dalton, "The Premenstrual Syndrome and Progesterone Therapy", William Heineman, ed., London, England (1984)], still others suggest no correlation at all [M. R. Mundy et al., Clin. Endocrinology, 14, pp. 1-9 (1981)]. Despite these disparities, relief of PMS symptoms has been reported after administration of progesterone to PMS patients.
The diagnosis of PMS is somewhat subjective because it is based on the occurrence of cyclical symptoms during the menstrual cycle. The treating physician must rely upon the patient to ascertain the occurrence and cyclicity of such symptoms, usually through the patient's charting of such symptoms on a daily basis for two or three menstrual cycles. Because each patient's analysis of whether or not she is suffering from a given symptom varies, it may be difficult to identify the disease in less severe cases of PMS. Moreover, in the more severe cases of PMS, the patient may be so disabled as to be unable to accurately chart her symptoms or unable to chart the symptoms at all.
Prior art biochemical tests for PMS are known in the art. For example, U.S. Pat. No. 5,093,265 to Portman et al., describes a test for measuring circulating antibodies to luteinizing hormone (LH) to diagnose PMS. M. E. Dalton et al., Postgraduate Medical Journal, 57, pp. 560-61, reports a correlation between PMS and sex hormone-binding globulin concentrations in women. Unfortunately, the accuracy and viability of these tests are questionable. Neither has been adopted by the medical community.
Thus, there remains a great need for an accurate biochemical test for the diagnosis of PMS.